1. Field
The following description relates to a method and apparatus for stable signal demodulation in a communication system.
2. Description of Related Art
Use of a sensor network to gather information is rapidly becoming widespread based on the fast improvement and commercialization of wireless network technology. Technological standardization of protocols that are used for wireless communication is also being actively conducted by entities such as the Institute of Electrical and Electronics Engineers (IEEE). In particular, standardization of wireless communication protocols such as Bluetooth, IEEE 802.15.4 and ZigBee is being performed. Such standardization helps devices to communicate with one another because in order for successful communication to occur between devices, it is necessary for the devices to agree on ways to transmit information using wireless signals and subsequently obtain the information from the signals.
A wireless sensor device may be used in various fields for many potential applications. For example, wireless sensor devices may be used in fields including home security, medicine, mobile healthcare, chemical and biological defect monitoring, breakdown and damage diagnosis for machinery, environmental monitoring, sensing information associated with natural disasters, intelligent logistics management, real-time security, remote observation, and the like. A wireless sensor is able to use sensor technology to gather information, and then use wireless communications technology to transmit the gathered information to be analyzed and interpreted.
Various wireless sensor networks and local area networks (LANs) require compact-sized sensors. For example, limited physical space may be available for sensors, and hence it may be necessary to use sensors that require minimal space. Also, for practical operation of a number of sensors, meeting low power and low complexity requirements is necessary. For example, sensors may have limited access to power, such as if they use a battery as a power source, and hence the sensors may need to ensure that they use a controlled amount of power to ensure that the power stored in the battery is not depleted too quickly. Similarly, if the sensors are too complicated, the infrastructure needed to support them may not be practical.
In particular, a sensor to be attached to or mounted on a human body needs to meet the low power and low complexity requirements as discussed above in a wireless body area network (WBAN), in which communication with an adjacent mobile device or a sensor of another human body is performed wirelessly.
To meet low power and low complexity requirements, a super-low power radio frequency (RF) structure may be used in lieu of a high power RF structure. However, the use of a super-low power radio frequency (RF) structure may lead to problems when trying to perform stable demodulation of a received signal.